iPhone 11 Bluetooth issues

Hi,

I’m having issues with Bluetooth connectivity in the last few months with headphones and in the car. Headphones always seem to randomly disconnect while in use and I have to forget device and search for device again in order to fix the problem or they’re just generally glitchy. When connecting Bluetooth in the car a few times it either doesn’t play at all but plays out loud on my phone even though Bluetooth says connected, now it’s started playing in the car for around 30 seconds or so and keeps disconnecting and I have to go onto the phone and press play in order for it to start again. Any ideas on a fix for this as it’s driving me mental. Thanks